nvme-cli/Documentation/nvme-get-property.1

'\" t
.\"     Title: nvme-get-property
.\"    Author: [FIXME: author] [see http://www.docbook.org/tdg5/en/html/author]
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 10/31/2024
.\"    Manual: NVMe Manual
.\"    Source: NVMe
.\"  Language: English
.\"
.TH "NVME\-GET\-PROPERTY" "1" "10/31/2024" "NVMe" "NVMe Manual"
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.SH "NAME"
nvme-get-property \- Reads and shows the defined NVMe controller property for NVMe over Fabric
.SH "SYNOPSIS"
.sp
.nf
\fInvme get\-property\fR <device> [\-\-offset=<offset> | \-O <offset>]
                        [\-\-human\-readable | \-H]
                        [\-\-output\-format=<fmt> | \-o <fmt>] [\-\-verbose | \-v]
                        [\-\-timeout=<timeout> | \-t <timeout>]
.fi
.SH "DESCRIPTION"
.sp
Reads and shows the defined NVMe controller property for NVMe over Fabric\&.
.SH "OPTIONS"
.PP
\-O <offset>, \-\-offset=<offset>
.RS 4
The offset of the property\&. One of CAP=0x0, VS=0x8, CC=0x14, CSTS=0x1c, NSSR=0x20
.RE
.PP
\-H
.RS 4
\-\-human\-readable: Show the fields packed in the property
.RE
.PP
\-o <fmt>, \-\-output\-format=<fmt>
.RS 4
Set the reporting format to
\fInormal\fR,
\fIjson\fR
or
\fIbinary\fR\&. Only one output format can be used at a time\&.
.RE
.PP
\-v, \-\-verbose
.RS 4
Increase the information detail in the output\&.
.RE
.PP
\-t <timeout>, \-\-timeout=<timeout>
.RS 4
Override default timeout value\&. In milliseconds\&.
.RE
.SH "EXAMPLES"
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
The following will run the get\-property command with offset 0
.sp
.if n \{\
.RS 4
.\}
.nf
# nvme get\-property /dev/nvme0 \-\-offset=0x0 \-\-human\-readable
.fi
.if n \{\
.RE
.\}
.RE
.SH "BUGS"
.sp
Currently the CAP value is truncated to 32 bits due to a limitation in the ioctl interface\&.
.sp
In a recent enough kernel, the 64 bit value is shown in kernel traces\&.
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
First enable traces by this command
.sp
.if n \{\
.RS 4
.\}
.nf
# echo 1 > /sys/kernel/debug/tracing/events/nvme/enable
.fi
.if n \{\
.RE
.\}
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Then look for NVMe Fabrics command (0x7f) at trace
.sp
.if n \{\
.RS 4
.\}
.nf
/sys/kernel/debug/tracing/trace
.fi
.if n \{\
.RE
.\}
.RE
.SH "NVME"
.sp
Part of the nvme\-user suite